Process of bcaking hypodermic syringes



Feb, 20, 1923.

1,445,641. F. x. NowAK.

PROCESS 0F MAKING HYPODERMIC SYRINGES.

FILED NOV. 3.xl9l9. 2 SHEETS-SHEET l.

Feb. 20,1923. 1,445,641. F. X. NOWAK. PROCESS; 0F MAKING HYPODERMIC sYmNGEs.

FILED NOV. 3.1919. 2 SHEETS-SHEET 2.

f5 .ation/w13 y Pai-@mea Fee. se, laas.

-`raras l titan FRANK X. Nowak, `orimooirnvn, NEW Yoan.

PROCESS OF MAKING HYPODEBMIC SYRIN'GES` Application filed ovember 3, 1919. Serial No. 335,393.

ToaZZ whom t may concern y Be it known that I, FRANK X. Nownmy a citizen of Republic of Austria, residingiat Brooklyn, N. Y., county of Kings, and Stateof New York,l have-invented certain new and useful Improvements in Processes of Mak# ing Hypodermic Syringes, of which the following is a specification. n 1

This inventionv relates to hypodermic syringes, and to a process ofmakingthe' same, thej invention relating particularly to the making; of hypodermic syringes having ground glass bodies. y t f Suchy ground glass vsyringes as have heretofore been constructedor suggested have been disadvantageous in various ways such as inability to accurately measure the amount of liquid discharged, or difliculty in removing the needle carrying element for cleaning purposes. These syringes have been constructed with their nozzle ends in the form of a frustum of a vcone projecting from they end of the syringe body, the needlecarrying element being adapted tor fitv over such projection. vGreat difficulty ris sometimes found in removing the needle carrying element -for cleaning or other purposes, thev adhesion between the parts being vso great that the coneshaped 'projecting end is frequently broken off.

, krThe present invention has for its object the production of a hypodermicsyringe having a'` glass body which permits both of accurate measuring' of the liquid discharged and of ready removal of the needle carrying element hout danger of breaking the glass body@ 1 'a j 4 The practical carrying out of my invenktion 4effected by"following out' a novel process whereby 'the forward end ofthe gl bodyis' given a Vshape which is novel in glass syringe bodies andv which was impossible of production with the ordinary methods'of making these glass bodies.

In fthe accompanying drawings I will illustratean apparatus suitable for carrying out my' novel process and the syringe as ob` tained by following out this process.

Figure l ofthe drawings is a plan view of the apparatus, omitting the hand operated forming tool. v l, Figure 2 is a fragmentary elevation show- `device. l

ing the initial stage in the forming operation.

vFigure 3 is an enlarged fragmentary longitudinal sectional view, showing the completed ,stepr of the forming operation. Figure tais an elevation ofthe cooling `Figure 5 is a transverse section on the line 3-3 of Fig.

, Figure 6 is a side view of the syringe complete. a

Figure 7 vis an enlarged fragmentar)v' longitudinal section of the syringe. v Figure 8 is a similar view of the glass body alone.

I will .first dcribed the syringe itself and then the process" of making it. The syringe comprises a ycylinder or body 1 of glass which is open at one end to receive the piston or plunger 2 also o-f glass.r The opposite end of the cylinder is provided with va thickened end wall 2 which extends straight across 7 such end. This endwall has a tapered axia opening 4 therethrough into which is fitted the correspondingly tapered end 5 of ,the carrier 6 for the needle, the needle beingV :red in the carrier in theusual manner while the usual aperture 8 extendsthrough both needle and carrier. The cylinder l preferably has a series of graduations 9 on thewall thereof which may indicate the quantity of liquid in the syringe in cubic centimeters or in any other desiredy measurement.

With the construction of cylinder as here shown, with the flat thickened end wall apeiu turedto receive the needle ycarrieran ideal arrangement is provided. The amount ot* liquid discharged can be accurately measured, the entire contents ofthe'syringe can be discharged, and the needle holder can be easily removed byA insertinga suitable implement in the open Aend of the cylinder and tapping on'. the end of the needle holder. ln order to enable thisfparticular form of glass syringe body to be produced l have devised a novel method of proceduren operating withv an apparatus which 'also presents' ufeatures of novelty. lj

The lsyringe bodies are formed from a length of glass tubing l0 1 which is freely supported by a series of rollers 1Q staggered asshownin'Figs.; and 5`so as to provide 105 opposed inclined surfaces between which lthe tubing rests. Those rollers :irc mounted to rotate freely on any suitable frames.

The 'glass tubing 10 is arranged With its end to be operated on extending between a pair of air pressure gas burners 13, having tips 14 arranged to direct the flames to points diametrically opposed on the glass tubing, as indicated by the arrows 15. Vithin the glass tubing near the end to be operated on, is an asbestos plug 16 which may for convenience be carried on the end of a rod 17 projecting through the tubing.

The end of the glass tubing projects beyoud the plug 16 a distance determined by experiment to be suine-'rent to provide the requisite' amount of 'glass for forming the end of the syringe body. The end faces of plug 16 forms one ot the walls between which the glass' is Worked or pressed to produce the desired structure, the other Walls being provided by a specially designed tool which is shown most clearly in Fig. 3.

This tool comprisesa rod or bolt 20' having an integral squarev tiane 21 nearone end thereof and a squarebld 22 adj ustably held on the opposite end by the nuts 22. `Secured to the block 22 areY the' rear ends ot a pair of fiat springs 23 which extend forwardly beyond the flangel 21 for adistance and have square inwardly facing plates 24 on `their forward ends, these plates having flat faces.

The portion of the bolt ,in front of the flange is in the form of a tapering pin 25, a taper of 88 to 1,000 being suitable. This portion is also preferably of octagonal cross sectionl asshown, the blunt edges formed by the apices of the ldiilerent faces assisting in the forming of the central opening to receive the needle holder.

In operation the tubing is positioned on the rollers 12 in position to have the projectj ing end portion thereoi1 receive the flames :from the' burners and While being heated the tubing is rotated, `Which may be accomplished by rolling it under the palni of the hand, the heat causing the end portion to contract and thicken as shown at 10 in Fig.2.lw

The forrriingy toolis then applied tothe heated end, bein@r held in the operators hand, the tapere pin 25 being inserted into the tube until the flange 21 bears against the end thereof and the springs con'ipressed to cause the plates to bearon the opposite sides of the tubing the rotation of which is continued. The plug 16 is provided with a recess 16 in its end to receiye the pin 25. The material is thus gradually pressed inward over the end ot the plug `16 and against the' flange 21 andpin 25, the parts n'allylassuming the position shown in Fig. 3 in which the forming of the needle carrying end iscoinpleted. As will be noted the plates 24 project partially over the plug 16 so that contraction ot the pla-tes beyond the level ot' the outer surface ot' the tubing. is prevented and a smooth exterior is niaintained to the extreme end of the syringe body.

After the end of the syringe body has been thus formed, the requisite length of tube to form the said body is severed in the usual manner from the main length and is placed in a 'cooling receptacle Where an even cooling, or even decrease in temperature, of the end Wall and adjacent portions di the side wall is ensured. This receptacle comprises a box 27 having an asbestos cover 28 in which is an opening of suicient size to frictionally receive *the glass body which is inserted therein with thel formed end Cl'ovtfn`` Ward, the box, or the interior thereof,being first heated by suitable means to a temperature approximately that of the heated glass. The box .is then allowed to cool, being'y preferably formed of or covered'o'r lined With material which does not conduct heat readily so that the cooling takes place slowly. By allowing the glass t'o cool this manner an even contraction of the material occurs and danger of cracking at the juncture df the end and side wall is ptevented. y i Attei-y the glass is cooled the entire inside surface is groundV to ensure an accurate fit of the various parts. j

Having thusy described invention, what claim as nevv and desire to secure by Letters Patent, is: L j

1. The process of forming a reduced bore on the end of` a glass tube, which consists in subjecting the end of alength of glass tubing to thel action of heat, and then coinpressing said end against ablock fitting Within the tube to form an internal flange on said end, and removing the block through the other end of the tube. A

2.. The process of forming a thickened end wall having a reduced bore therein on the endv of a glass tube which consists in subjecting the end ot a length of glass tubing to the action of heat7 inserting a blockiivthin said tube, compressing the heated end ot' the tube against` said block and about a tapered pin to'forrn said reduced bore and removing the block through the other end of the tube. y i

The process of forming a thickened end wall. having a reduced bore therein on the end ot a g tube, with the inner side of said wall lforming a right angle with the bore ot said tube which consists in subjecting the end of a lengthof glasstubin'gi to the action of heat, compressing" the heated end of the tube between a pairv of blocks, one ot which is inserted Within said tube and about a tapered pin located between said blocks, simultaneously 'subjectingJ the periphery of the tube to pressue to form the glass about said tapered pin and to fill the space between the blocks and thereafter removing the blocks in opposite directions from the ends of thev tube.

4. A means for forming glass bodies for hypodermc syringes comprising a Cylindrical plug with a flat end Wall adapted to be inserted in a glass tube, and a tool comprising 'a tapered pin adapted for insertion in the end of the tube, a member fixed to said pin having a surface at right angles to the axis of the pin, and a pair of transversely movable plates extending forwardly from points adjacent said surface on opposite sides of the said pin.

In testimony whereof I have aflxed my signature.

FRANK X. NOWAK. 

